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A field screening of eight genotypes at farmer’s field of Sundarbazar, Lamjung in randomized complete block design with three replications was conducted to study the character association between yield and yield attributing traits of rice and their direct and indirect effect on grain yield under reproductive drought stress condition from June to November 2018. The analysis of variance revealed significant differences for all traits except plant height, which indicates existence of genetic variability, potential for selection and further improvement among all genotypes under study. Correlation and path analysis revealed that flag leaf area, chlorophyll content, days to heading and thousand grain weight showed significant and positive association as well as positive direct effect on yield of rice which means direct selection of these traits would be beneficial for the improvement of grain yield facilitating the selection and progress on breeding program.

Rice (Oryza sativa L.) is a species of crops which is highly sensitive to drought. The sensitivity to water stress varies from genotypes to genotypes of rice. An experiment was performed to compare twenty-five different rice genotypes for drought tolerance in the seedling stage at Gokuleshwor Agriculture and Animal Science College, Baitadi Nepal from July to August 2018. The genotypes were tested under two conditions viz., water stress and non-water stress. The research work was carried out in a completely random design (CRD) with three replications. The results exhibited the height of seedling, length & breadth of leaf, number of leaves/plant decreased, and number of leaves shedding increased under water stress condition. Clustering was done by the method of average linkage, and genotypes were categorized into five clusters. The genotype, namely Radha 11 grouped in Cluster-V had higher plant height, bigger length & breadth of leaf, maximum number of leaves/plant and minimum number of leaf shedding. Thus, this genotype showed the best performance for morphological traits under water stress condition. Therefore, this genotype Radha 11 can be utilized further for developing rice variety with drought-tolerance.

To assess correlation and to find out the direct and indirect effect of yield attributing traits on grain yield, thirty wheat (Triticum aestivum L.) genotypes were experimented at Kamalamai-04, Phant, of Sindhuli district, Nepal. The experiment was laid out in alpha-lattice design with three replications. Thirteen quantitative traits including grain yield of wheat were studied during this study. The grain yield of wheat has significant (P≤0.01) and positive genotypic and phenotypic correlation with number of spikes per meter (0.6**, 0.47**), grains per spike (0.69**, 0.65**), weight of grains per spike (0.69**, 0.61**), thousand kernel weight (0.87**, 0.74**), maturity days (0.5*, 0.47**), above ground mass yield (0.96**, 0.83**) and harvest index (0.93**, 0.64**) of wheat. The genotypic correlation is higher in magnitude than the phenotypic correlation for almost all the studied traits. Path analysis of genotypic correlation showed a high positive direct effect of plant height (0.75), above ground biomass (0.6), spike length (0.43), and harvest index (0.29) on grain yield of wheat. Hence, for increasing yield of wheat in the breeding program, selection and hybridization can be made more effective and accurate by using those traits that have a significant positive correlation coefficient and direct effect on the grain yield of wheat.

The performance of eleven rice genotypes along with local check variety was studied at the field of IAAS Lamjung campus. The experiment was conducted under two field conditions i.e., drought stress and non-stress conditions. Grain yield was recorded in both experiments stress (Ys) and non-stress (Yns) at maturity. From grain yield data, some drought tolerance indices such as Stress Tolerance Index (STI), Stress Susceptibility Index (SSI), Drought Tolerance Efficiency (DTE%), Yield Stability Index (YSI), Mean Productivity index (MPI), Geometric Mean Productivity (GMP) were calculated. A genotypic correlation was also calculated for grain yield and all indices. Grain yield under stress conditions (Yns) was positively and significantly correlated with MRP, MPI, GMP and STL. Similarly, a positive and significant association has also been observed between grain yield under stress condition and MPI, MRP, STL and GMP. So, they were the best predictor of potential yield Yns and Ys than SSI, DTE, YSI. Among the eleven rice genotypes Khumal-8, Khumal-7 and IR87760-15-2-3-4 were selected as the superior genotypes for the development of drought-tolerant cultivar in the future breeding programs.

An experiment on eleven rice genotypes was designed at field of Institute of Agriculture and Animal Science, Lamjung, under randomized complete block design with three replications from June-October, 2018 to study genetic variability and character association. Analysis of variance showed significant difference among the genotypes for all the characters studied except for grain yield and fertility percent which indicates the existence of sufficient genetic variability and potential for selection and further improvement. Grain yield was significantly positively correlated with panicle length while positively and non-significantly correlated with days of flowering, leaf area and straw yield except for plant height, SPAD60, fertility percent, thousand grain weight and effective tillers. Leaf area had maximum positive direct effect on grain yield followed by panicle length, thousand grain weight and effective tillers which indicates help for selection and improvement of rice genotypes. The higher value of correlation between panicle length and grain yield is due to the direct effect of panicle length which exhibit true relationship between them. The variability study showed that there was high genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) for thousand grain weight. High heritability estimates coupled with high genetic advance as per percentage of mean (GAM) was found for thousand grain weight, days of flowering, leaf area and effective tillers which indicate the control of additive gene of action and a greater scope of selection for crop improvement.

A study was conducted to evaluate the effect of different doses of nitrogen and phosphorus on the growth and development, flower spike characteristics and the vase life of gladiolus (Gladiolus grandiflorus L.) at the horticulture farm, IAAS, Rampur, Nepal, in 2014–15. One of the promising varieties, American Beauty, was used as the planting material in this experiment. Observations on the plant height, leaf number, length of spike and rachis, diameter of spike, number of florets on the spike and diameter of corm were taken to assess the effect of different combinations of nitrogen and phosphorus on gladiolus plants. The variable doses of nitrogen (75, 100 and 150 kg/ha) and phosphorus (50, 75 and 100 kg/ha) and their interaction produced a significant effect on the germination of corms and growth (height) of the plants. Nitrogen and phosphorus combination significantly affected the number of leaves during earlier stages of the plant growth. The combination of nitrogen and phosphorus did not cause significant increment on corm diameter. The higher doses of nitrogen produced a significant difference on the length of flower spikes, rachis length, spike diameter and floret width. However, the effect was found to be non-significant on number of florets on the spike. The variable doses of sucrose solution produced significant effect on the total vase life of the flower spike at room temperature. The combination 150 kg/ha nitrogen and 100 kg/ha phosphorous produced highest plant height (66.57 cm) at 75 days after planting, spike length (76.54 cm), rachis length (43.55 cm) and combination of 100 kg nitrogen/ha with 75 kg phosphorous/ha gave longest vase life (8.5 days) of cut spike (in 6% sucrose solution) as compared to the other treatments under study. Thus, the variable application of nitrogen and phosphorus significantly affects the growth, development and vase life of gladiolus. Keywords: Gladiolus, nitrogen, phosphorus, spike, vase life Cite this Article Krishna Dhakal, Dinesh Khanal, Dipendra Kumar Ayer et al . Effect of Nitrogen and Phosphorous on Growth, Development and Vase Life of Gladiolus. Research & Reviews: Journal of Agricultural Science and Technology . 2017; 6(3): 1–7p.